Several of you have written with questions about DHA, a type of Omega-3 fat that’s important for healthy brain function. We know that DHA is important for the development of a baby’s brain, both before and after birth. And lately, it’s been proposed as a possible treatment for ADHD and as a hedge against Alzheimer’s disease—two very different disorders that are both on the rise. Could DHA be the secret to a healthy brain throughout life? Let’s take a look at the latest research and figure out how this nutrient fits into your diet.

DHA: The Brainy Member of the Omega-3 Family

As I talked about in my show on Fish Oil and Omega-3s, omega-3 isn’t a single nutrient but a whole family of fatty acids. Two of the most biologically active members of the omega-3 family are EPA and DHA. When you eat fish—or take a fish oil supplement—you’re getting some of each.

At the risk of over-simplifying a complex area of nutritional biochemistry, EPA helps keep your heart and blood vessels healthy, while DHA supports your brain and neurological function. So it makes sense for researchers to look for connections between DHA intake and cognitive disorders like ADHD and Alzheimer’s disease. But before you head to the vitamin shop, let’s see what they’ve found.

DHA and ADHD

Several researchers have observed that kids with ADHD have lower levels of omega-3s, including DHA, in their cells and bloodstream. If ADHD might be due, even in part, to DHA deficiency, then we could hope that increasing DHA intake might be helpful. But there’s also some evidence that these lower blood levels aren’t due to lower intake but due to some sort of problem with fatty acid metabolism—in which case, increasing intake wouldn’t do any good. In a few studies where they’ve given omega-3 supplements to kids with ADHD, only small improvements were seen.